This invention relates generally to the field of chemical processing, particularly of toxic, volatile or otherwise dangerous substances, and more particularly to an improved process sampler by means of which small quantities of substances to be examined may be removed from a reacting mass for analysis at convenient intervals during a processing cycle. Devices of this general type are known in the art, and the invention lies in specific constructional details which afford increased convenience with regard to the recycling of a tested sample, and more importantly, increased safety to the technician or operator conducting the sampling operation.
The need for obtaining uncontaminated representative samples of chemical processing operations has been one of long standing. The most common method employed involves the use of a so-called dip tube which is projected through or mounted within an orifice in the reactor vessel. Where the sampled material is not particularly dangerous, this structure has proved adequate.
More sophisticated sampling devices include those sold under the trademark DOPAK. These devices include a means for connecting into the process line at a suitable point which means includes a valve to control flow to a sample container. Adjacent the valve is a pair of hollow needles both of which penetrate a self-sealing diaphragm or septum located beneath the threaded cap of the sample container. One needle feeds the sample, while the other needle exhausts air or other displaced fluid within the container. When the container is filled with a sample to desired volume, the container is disconnected from the needles without spillage.
Another type of sampling device is marketed under the trademark POSACON. This type of device is installed in line with a conduit, and includes a transversely arranged needle valve which communicates with a selectively engageable piston injector which operates somewhat in the manner of a hypodermic syringe. The injector has means for closing the same against leakage before disconnecting from the valve body.
In both types of devices, above-described, after examination and/or testing of the sample, there remains the problem of disposing of the unused portion thereof which may create environmental problems, particularly where the samples are corrosive, toxic, or otherwise dangerous.